The invention concerns an electronically commutated motor for dust exhausters, vacuum cleaners or similar devices having a stator with excitation windings and a rotor positioned to rotate in an air gap. The rotor has bundled laminations and permanent magnets around its circumference matching the number of poles of the stator. Furthermore, a fan rotor is also provided on the rotor shaft as a ventilator and the rotor shaft is connected to a turbine to generate an intake air current.
In electrical motors, and especially in dust exhausters and contaminant removal systems or similar devices, commutated or brushless motors which operate with high performance are already known, but have the disadvantage, particularly in the high-speed ranges, of not having the necessary operational safety. The prior art motors definitely do have high starting torque; however, they disadvantageously have a relatively unfavorable performance volume ratio and require a lot of space, particularly in devices designed for manual use.
The designs of prior art motors also have the disadvantage that the motor or bearings will run hot, particularly when a turbine must also be driven, as a result of high motor performance and the resultant heat which is released. In particular, prior art motors have an inadequate introduction of cooling air for the motor and for the bearings of an associated turbine.
The objective of the present invention is therefore to design an electronically commutated motor in such way that achieves an increased speed, with a particularly safe design of the motor and the turbine, regardless of the starting torque at high performance levels, and with no danger of the motor, the motor bearings, or the turbine bearings running hot.